Abstract: A bidirectional optical module according to the present invention comprises light emitting elements 110, 130 that emit light to enter an optical fiber 71, a light receiving element 190 that receives light having exited the optical fiber 71 and a light branching element 160 that guides the light having exited the optical fiber 71 onto the light receiving element 190. It further includes a stray light shielding member 185 disposed between the light branching element 160 and the light receiving element 190 and having formed therein an opening 186, through which the light to enter the light receiving element 190 passes. The stray light shielding member 185 blocks stray light 100b while light 100a having exited the fiber 71 passes through the opening 186. Therefore, any increase in the extent of error in the detection of the returning light level or the position of a reflecting point is prevented.

Abstract: A bidirectional optical module according to the present invention emits light to an optical fiber and allows returning light from the optical fiber to enter and includes a plurality of light emitting elements that emit light to enter the optical fiber, a light receiving element that receives light having exited the optical fiber, and a non-reciprocal unit for making an optical path in a forward direction from the light emitting element to the optical fiber and an optical path in a backward direction from the optical fiber to the light emitting element different. Then, polarization planes of light incident on the optical fiber after being emitted from the plurality of light emitting elements are mutually orthogonal, and the non-reciprocal unit emits returning light of light emitted from the plurality of light emitting elements from the optical fiber toward the light receiving element to one light receiving element.

Abstract: A bidirectional optical module according to the present invention emits light to an optical fiber and allows returning light from the optical fiber to enter and includes a plurality of light emitting elements that emit light to enter the optical fiber, a light receiving element that receives light having exited the optical fiber, and a non-reciprocal unit for making an optical path in a forward direction from the light emitting element to the optical fiber and an optical path in a backward direction from the optical fiber to the light emitting element different. Then, polarization planes of light incident on the optical fiber after being emitted from the plurality of light emitting elements are mutually orthogonal, and the non-reciprocal unit emits returning light of light emitted from the plurality of light emitting elements from the optical fiber toward the light receiving element to one light receiving element.

Abstract: A bidirectional optical module according to the present invention comprises light emitting elements 110, 130 that emit light to enter an optical fiber 71, a light receiving element 190 that receives light having exited the optical fiber 71 and a light branching element 160 that guides the light having exited the optical fiber 71 onto the light receiving element 190. It further includes a stray light shielding member 185 disposed between the light branching element 160 and the light receiving element 190 and having formed therein an opening 186, through which the light to enter the light receiving element 190 passes. The stray light shielding member 185 blocks stray light 100b while light 100a having exited the fiber 71 passes through the opening 186. Therefore, any increase in the extent of error in the detection of the returning light level or the position of a reflecting point is prevented.